Hackers have obtained hundreds of millions of log-ins – and are flogging them on the dark web

Hack attack – what happened?

Log-in details for roughly 617million online accounts have turned up for sale on the dark web.

The passwords are encrypted and so can't immediately be used, but hackers can crack them and then gain access to your website.

The huge cache of log-ins is retailing for about £15,500, and was first spotted by tech site The Register.

That might sound like a high price, but buyers will be hoping that people re-use these passwords across multiple apps – giving them a golden ticket into more prized accounts, like banking apps. This is called "credential stuffing".

Hack attack advice – what you should do NOW

"Passwords are to the digital age what seatbelts were to the auto industry.

"They protect your identity, finances, and other critical personal information – so should they be cracked and used, all this data could be used for nefarious means.

"Given the sheer quantity of this data on sale, we would advise all consumers, not just those affected, to change their passwords immediately across all of their accounts.

"For those affected, this is even more important.

"You may not be able to control the security architecture of the digital services you use every day, but you can take measures to make sure you have optimal password hygiene.

"This is the digital version of the 'containment' doctrine.

"Best practice password hygiene calls for unique and complex passwords for each and every account, which ensures that if one account is breached, then your other accounts will be secure.

"Some breaches, as we see here, aren't discovered or disclosed for months or even years, so in addition to this, changing your passwords regularly is crucial, as you never know when your account might have been exposed."

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